In a general wireless communication system of 3GPP (Third Generation Partnership Project), user equipment (UE) connects to a core network (CN) via a NodeB and a radio network controller (RNC).
An area which is formed by the NodeB and in which wireless communication is enabled is usually a cell with a relatively large radius, which is referred to as “macro cell”. In the 3GPP, addition of a small cell referred to as “femto cell” to a wireless communication network including such a general configuration has been considered (see Literature 1).
For example, an architecture has been considered in which an HNB (Home NodeB) is appropriately arranged as a small NodeB forming the femto cell, and the BNB is connected to an HNBGW (HNB Gateway) via a public wired network. For example, the HNB is installed in an indoor area such as at home or a company.
The HNBGW is a relay apparatus that relays data mutually transmitted and received between the HNB and the core network, and is logically arranged between the HNBGW and the core network. The HNB is also connected to an HMS (HNB Management System) via the public wired network. The HMS is a management apparatus that manages a parameter of the HNB and configuration information on the HNB. Generally, the HNBs can belong to the HNBGW and the HMS.
FIG. 18 is a block diagram showing a configuration example of a wireless communication system that deploys both the macro cells and the femto cells. With reference to FIG. 18, this wireless communication system includes NodeBs 501 and 502, RNC 701, HNBs 101 and 102, HNBGW 301 and HMS 401. NodeBs 501 and 502 form macro cells 601 and 602, and HNBs 101 and 102 form femto cells 201 and 202, respectively.
NodeBs 501 and 502 are connected to RNC 701, and RNC 701 is connected to core network node 901.
HNBs 101 and 102 are connected to HNBGW 301 and HMS 401 via public wired network 1000. HNBGW 301 is connected to core network node 901. Here, while the example is shown in which HNB 101 and HNB 102 are connected to same HNBGW 301 and same HMS 401, HNB 101 and HNB 102 may also be configured to be connected to a different HNBGW and a different HMS, respectively.
In the wireless communication system in such a configuration, UE 802 can preferably connect to all of NodeBs 501 and 502 as well as HNBs 101 and 102, and furthermore, can preferably perform handover among them. In a 3GPP-WCDMA system, an SRNS Relocation Procedure is used for the handover (see Literature 5), and thus execution of this procedure is preferably enabled.
Moreover, in the future, introduction of SON (Self-Organizing Networks) is expected as a function of constructing a network configuration without the need for manual input by an operator, or with a minimum amount of manual input by an operator (see Literature 2). For example, automatic neighbour cell relation construction (see Literature 3), a self-optimizing network configuration (see Literature 4) and the like have drawn attention.